Dalton Trumbo himself might declare "Trumbo," the handsome docu adaptation of son Christopher's play of the same title, a bit tame and more than a tad subdued.

Dalton Trumbo himself might declare “Trumbo,” the handsome docu adaptation of son Christopher’s play of the same title, a bit tame and more than a tad subdued. This portrait of one of Hollywood’s fieriest and most cantankerous screenwriters might seems like old news to Hollywood cinephiles and informed students of the blacklist era, but it willserve as a fine entry point for younger auds interested in learning about theprice paid by moviemakers and their families swept up in the 1950s anti-Communist net. Fests, microdistribs and culture-vulture cablers should be a lock.

Christopher’s 2003 play (originally starring Nathan Lane as Trumbo) derives from the 1999 volume of Trumbo’s collected letters, “Additional Dialogue” — though “monologue” is a more apt term, since the letters comprised the play’s text. New doc reps a continuity from that project, with the play’s helmer, Peter Askin, working behind the camera, Christopher authoring the screenplay and Lane once again portraying Trumbo as a slightly puckish figure.

Striking changes abound, however: Eight additional actors join Lane to read from a wide range of letters that cover the crucial personal (though not necessarily artistic) years for the scribe from the late 1940s to the early 1960s. Woven into these perfs, which are elegantly and emotionally essayed along with Lane by Brian Dennehy, Joan Allen, Paul Giamatti, David Strathairn, Donald Sutherland, Josh Lucas, Liam Neeson and Michael Douglas, are exceptionally well-selected interview clips with Trumbo (largely from the doc “Dalton Trumbo: Screenwriter”), archival footage of the “Hollywood Ten” hearings stage-managed by Sen. Joseph McCarthy, and touching Trumbo homemovie footage.

Trumbo’s early success, with such pics including “Thirty Seconds Over Tokyo” (archly re-created in the finale of “Pearl Harbor”), is perhaps overstated. Though he rapidly earned a solid rep in studio circles as a reliable scripter with a distinctive voice, few of his scripts will ever land in a screenwriter’s Hall of Fame, though the doc is based on the implicit assumption that Trumbo was a master. A lively Kirk Douglas, instrumental in breaking the blacklist and getting Trumbo onscreen credit for “Spartacus,” exaggeratedly says of his pre-Cold War worth: “He was probably the best writer of that time.”

Pic offers no fresh insight into McCarthy’s shockingly successful moves to force the studios to blacklist Trumbo’s comrades, though it’s instructive that the “Ten” insisted on their First (free speech) and not Fifth (non-self-incrimination) Amendment right — a fine difference for some, but a philosophically huge one for Trumbo. Clips from not only the exhaustively well-known “I Am Spartacus!” scene but also less-remembered scenes from “The Sandpiper,” “Johnny Got His Gun” and “The Fixer” offer examples of how Trumbo liked to insert into scripts his beliefs for free speech and against ratting on one’s own.

Most affecting, along with the elegant (Allen, Neeson), impassioned (Strathairn, Dennehy) and witty (Giamatti, Lane) readings are interviews and insights with Christopher and particularly sister, Mitzi, who describe not only the financially precarious situation for their clan as they packed up and left Los Angeles for exile in Mexico with other “Ten” families, but the tragic outcomes for several blacklist victims. Manner in which the blacklist was actually broken is painted in a frustratingly vague terms, with Otto Preminger, whose Trumbo-penned “Exodus” was made simultaneously to “Spartacus,” demoted to a supporting role.

Project has been nurtured with considerable care, from classy lensing care of a team of four (Frank Prinzi, Jonathan Furmanski, Fred Murphy, Chris Norr) to a gentle, thoughtful piano score by Robert Miller.